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101.
Marek Barski 《Structural and Multidisciplinary Optimization》2006,31(3):211-222
In this paper, the problem of optimal design of shells against instability is considered. A thin-walled shell is loaded, in
general, by overall bending moment, constant or varying along an axis of a shell, by the appropriate shearing force and by
an axial force and a constant torsional moment. We look for the shape of middle surface as well as the thickness of a shell,
which ensures the maximum critical value of the loading parameter. The volume of material and the capacity of a shell are
considered as equality constraints. The concept of a shell of uniform stability is applied. 相似文献
102.
103.
A convenient synthetic procedure for preparing nickel carboxylated phthalocyanine is reported. Upon further hydroxylation, such metal phthalocyanine moieties are incorporated into several melamine-based polyester high-solids systems and the structure—property correlations are examined. Molecular level spectroscopic FTIR analysis and mechanical testing are correlated in an effort to establish structure—property relations in these coatings. It is found that the presence of metal phthalocyanine macrocycle as a cross-linking agent enhances such properties as adhesion, hardness, and impact resistance. © 1993 John Wiley & Sons, Inc. 相似文献
104.
Marek Berezowski Krzysztof Warmuziski 《Chemical Engineering and Processing: Process Intensification》1993,32(6):345-347
A method is proposed for increasing the dedusting efficiency of cyclones. The method, which is based on the introduction of the gas undergoing purification into a recycle loop, is of considerable practical importance as it enables the process to be controlled so as to maintain a constant efficiency of dust removal. 相似文献
105.
The temperature behaviour of both cadmium and nickel oxide electrodes of the sintered type (as used in sealed NiCd cells) has been investigated 相似文献
106.
107.
108.
Lech Winnicki Marek Kwieciski Micha Kleiber 《International journal for numerical methods in engineering》1977,11(3):553-561
Full limit analysis is preseted of a thin plate under plane stress, perforated with circular holes arranged in a regular penetration pattern. The material is assumed to be elastic–perfectly plastic and to obey the Huber–Mises yield condition together with its associated flow law. The finite element tangential stiffness method is employed. Triangular constant-strain elements are used, the load being generated by means of constant edge displacements at the periphery of a suitably selected subregion. Load-displacement diagrams are obtained for various edge displacement programs and then an interaction curve is constructed for the perforated plate considered. Each computational step is associated with a certain plastic zone which develops until the limit state configuration is reached. The plate is provided with equilateral triangular configuration of holes with arbitrary cutout coefficients. The interaction curves are plotted against the Huber–Mises yield condition for the plate without openings. 相似文献
109.
110.
The possibility of the occurrence of critical point in /Agl-xKx/NbO3 solid solutions is discussed. 相似文献